Packed beds of "active" powders or granules are commonly used to treat liquid or gas streams using gravity or pressurized flow. These loose materials are used in packed beds, which commonly experience large pressure drops, especially in the case where the bed particle size is small. However, small particle sizes are desirable in that they increase process performance by improving material utilization effectiveness and packing density.
In many processes packed bed columns of considerable length are sometimes required. However, with increasing column length, the flow rate decreases. Also, such columns develop channeling of the feed solution, which decreases process efficiency. Packed beds also have issues with material attrition (losing small particles).
A wide variety of active granule or powder materials are used in industrial applications, some of which include: ion exchange materials (zeolites, organic resins, gamma alumina, etc); adsorption materials (carbon, zeolites, clays, etc); purification materials (iodinated resins, Ag-impregnated materials, etc.); chemical and biological reaction materials (enzymes, proteins, carbon, biochemical materials, etc.); and catalyst materials (unsupported or supported platinum group metals and compounds, transition metals and compounds, alkali metals and compounds, alkaline earth compounds, rare earth compounds etc).
Accordingly, a need exists for efficient devices in which the disadvantages of loose powder or granular or loosely bound materials are eliminated and in which the disadvantages of decreased flow large packed beds and decreased efficiency due to channeling are eliminated.
The present invention provides such a device and method.